Bus arrangement and method for operating a bus arrangement

ABSTRACT

A bus arrangement includes a coordinator; a first subscriber; a first subscriber arrangement with a second subscriber; and a bus. The bus couples the coordinator with the first subscriber and the second subscriber. The first subscriber is arranged between the coordinator and the second subscriber on the bus. The bus arrangement is configured such that the first subscriber arrangement can be decoupled from the bus in an operating phase, and such that the first subscriber cannot be decoupled from the bus in the operating phase.

CROSS-REFERENCE TO PRIOR APPLICATIONS

This application is a U.S. National Stage Application under 35 U.S.C. §371 of International Application No. PCT/EP2016/079835 filed on Dec. 6,2016, and claims benefit to German Patent Application No. DE 10 2015 121292.7 filed on Dec. 7, 2015. The International Application was publishedin German on Jun. 15, 2017 as WO 2017/097737 A1 under PCT Article 21(2).

FIELD

The present invention relates to a bus arrangement and to a method foroperating a bus arrangement.

BACKGROUND

A bus arrangement can be used in automation technology, for example. Abus arrangement typically has one coordinator and a plurality ofsubscribers. The subscribers can be embodied as actuators or sensors.The actuators can be switching devices such as contactors, motorstarters and circuit breakers, command devices and frequency converters.

SUMMARY

In an embodiment, the present invention provides a bus arrangement thatincludes a coordinator; a first subscriber; a first subscriberarrangement with a second subscriber; and a bus. The bus couples thecoordinator with the first subscriber and the second subscriber. Thefirst subscriber is arranged between the coordinator and the secondsubscriber on the bus. The bus arrangement is configured such that thefirst subscriber arrangement can be decoupled from the bus in anoperating phase, and such that the first subscriber cannot be decoupledfrom the bus in the operating phase.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be described in even greater detail belowbased on the exemplary figures. The invention is not limited to theexemplary embodiments. Other features and advantages of variousembodiments of the present invention will become apparent by reading thefollowing detailed description with reference to the attached drawingswhich illustrate the following:

FIGS. 1 and 2 illustrate embodiments of a bus arrangement;

FIGS. 3A to 3H illustrate an embodiment of a bus arrangement indifferent phases; and

FIG. 4 illustrates an exemplary chronological sequence of phases in abus arrangement.

DETAILED DESCRIPTION

An embodiment of the present invention provides a bus arrangement and amethod for operating a bus arrangement in which subscribers are coupledin different manners with a bus.

In one embodiment, a bus arrangement includes a coordinator, a firstsubscriber, a first subscriber line with a second subscriber, and a bus.The bus couples the coordinator with the first and second subscribers.The first subscriber is arranged between the coordinator and the secondsubscriber on the bus. Here, the bus arrangement is designed(configured) such that the first subscriber arrangement can be decoupledfrom the bus in an operating phase.

In one embodiment, the bus arrangement is not designed (configured) suchthat the first subscriber can be decoupled from the bus in an operatingphase.

The coordinator advantageously continues the operating phase even afterdecoupling of the first subscriber arrangement.

In one embodiment, the first subscriber arrangement and thus the secondsubscriber can be decoupled and coupled in an operating phase. The firstsubscriber arrangement and the second subscriber are thus hot-pluggable.In contrast, the first subscriber cannot be decoupled or coupled in anoperating phase. The first subscriber is not hot-pluggable.

The first subscriber arrangement can also be referred to as a drawer.

In one embodiment, the coordinator outputs a first error message and/orputs the bus device in a secure state if the first subscriber is activeat a first timepoint during an operating phase and has been removed oris inactive at a second timepoint during the same operating phase. Asecure state can be achieved by switching off all subscribers of the busarrangement, for example. Here, the second timepoint comes after thefirst timepoint.

In one embodiment, the coordinator registers the decoupling of the firstsubscriber arrangement if the second subscriber is active at a firsttimepoint during an operating phase and has been removed or is inactiveat a second timepoint during the same operating phase. Here, the secondtimepoint comes after the first timepoint. The coordinator registers thedecoupling of the first subscriber arrangement in a non-volatilesemi-permanent memory of the coordinator, for example.

In one embodiment, the first subscriber and the first subscriberarrangement are mechanically intercoupled such that the first subscriberarrangement can be decoupled from and coupled with the bus withoutremoval of the first subscriber and the first subscriber cannot bedecoupled from and coupled with the bus without removal of the firstsubscriber arrangement. This prevents the first subscriber arrangementfrom being connected to the bus without the first subscriber beingconnected to the bus.

The first subscriber can be embodied as a control branch.

The first subscriber can include a power supply that is independent fromthe coordinator and supply the first subscriber arrangement withelectric power.

The first subscriber can be embodied in such a way that it is difficultto separate mechanically from the bus arrangement.

In an alternative embodiment, the coordinator places different flags inthe non-volatile semi-permanent memory for the first and secondsubscribers. The flags indicate decouplability and couplability in anoperating phase. The flags prevent the first subscriber arrangement frombeing connected to the bus and activated without the first subscriberbeing connected to the bus.

In one embodiment, the first subscriber includes a first non-volatilepermanent memory in which a first serial number is stored. Moreover, thesecond subscriber includes a second non-volatile permanent memory inwhich a second serial number is stored.

In one embodiment, in a configuration phase, the coordinator assigns thefirst subscriber a first subscriber address and the second subscriber asecond subscriber address. In addition, the coordinator also retrievesthe first and second serial numbers and stores them in a non-volatilesemi-permanent memory of the coordinator. The coordinator can store therespective serial number for each subscriber address. In thenon-volatile semi-permanent memory, the first subscriber address isassociated with the first serial number and the second subscriberaddress is associated with the second serial number, and so on. Asubscriber address can also be referred to as a subscriber number.

Advantageously, the first and second subscribers have unique serialnumbers. Since the first subscriber differs from the second subscriberbased on the respective serial number, it is possible to address thesubscribers using the serial numbers. The first serial number is aglobally unique number that is stored in the first subscriber during theproduction process of the first subscriber. Accordingly, the secondserial number is also a unique number that is stored in the secondsubscriber during the production process of the second subscriber.

In one embodiment, the first subscriber can be addressed using the firstsubscriber address and the first serial number. The second subscribercan only be addressed using the second subscriber address and not usingthe second serial number.

In one embodiment, the non-volatile semi-permanent memory of thecoordinator remanently stores the first and second serial numbers. Thenon-volatile semi-permanent memory of the coordinator thus continues tostore the first and second serial numbers even if the power supply ofthe coordinator is interrupted.

In one embodiment, the configuration phase is part of an operatingphase. The operating phase is followed by a shut-down phase and thenanother operating phase, which begins with a restart phase.Subsequently, additional operating phases, each of which has a restartphase at the beginning, can alternate with shut-down phases. The restartphase thus follows the configuration phase. The coordinator can alsoreceive a command via a switch of the coordinator, for example to startanother operating phase with an additional configuration phase.

In one embodiment, in a restart phase following the configuration phase,the coordinator establishes a connection to the first and secondsubscribers, retrieves the first and second serial numbers, and comparesthe retrieved first and second serial numbers with first and secondserial numbers stored in the non-volatile semi-permanent memory of thecoordinator. For example, the coordinator can output a signal with anerror message if one or both retrieved serial numbers deviate from thestored serial numbers. With this signal, the coordinator can inform anoperator of the bus arrangement or a higher-level control of the busarrangement that one of the subscribers has been exchanged.

A shut-down phase precedes the restart phase. Exchanging the first orsecond subscriber changes one of the serial numbers. The coordinator canthus advantageously determine whether, for example, a subscriber hasbeen exchanged during the shut-down phase before the restart phase.

In one embodiment, the exchanging of the first subscriber during ashut-down phase is only permitted if an additional configuration phaseis carried out after the exchange.

In one embodiment, the first subscriber is exchanged for another firstsubscriber during a shut-down phase that lies between the configurationphase and the additional configuration phase. In the additionalconfiguration phase, the coordinator establishes a connection to theadditional first subscriber, retrieves a serial number of the additionalfirst subscriber, and stores it in the non-volatile semi-permanentmemory in place of the first serial number. The additional firstsubscriber thus takes the place of the first subscriber.

In one embodiment, the coordinator includes a switch. The coordinatorcarries out the additional configuration phase after actuation of theswitch.

In one embodiment, the coordinator can be put into an exchange operatingphase or exchange mode or replacement mode. If the coordinator is in theexchange operating phase, then the coordinator establishes a connectionto the second subscriber, retrieves the second serial number, and storesthe retrieved second serial number in the non-volatile semi-permanentmemory in place of the previously stored second serial number. Forexample, in an exchange operating phase, the first subscriber cannot beexchanged, since that occurs exclusively in an additional configurationphase. In the exchange operating phase, however, it is possible for thefirst or another subscriber arrangement or individual subscribers to beexchanged in the first or another subscriber arrangement.

In one embodiment, the bus arrangement includes an additional subscriberthat is connected to the bus between the coordinator and the firstsubscriber in the configuration phase and removed after theconfiguration phase. In a restart phase after the configuration phase,the coordinator addresses the first subscriber using the first serialnumber and assigns it a first subscriber address.

Advantageously, the gap that results from the removal of the additionalsubscriber is filled by addressing the first subscriber with its firstserial number.

The additional subscriber can be part of an additional subscriberarrangement. The additional subscriber can be the direct predecessor ofthe first subscriber.

In one embodiment, the first subscriber activates the second subscriberin the restart phase. The coordinator assigns the second subscriberaddress to the second subscriber and retrieves the second serial number.If the retrieved second serial number matches the second serial numberstored in the non-volatile semi-permanent memory of the coordinator, thecoordinator activates the second subscriber. Otherwise, the coordinatoroutputs an error message and/or deactivates the second subscriber.

In one embodiment, the bus includes a first signal line that couples thefirst subscriber and the coordinator, and a bus line that connects thesecond subscriber to the first subscriber. The bus includes at least onebus line that connects the coordinator to the first and secondsubscribers.

In one embodiment, in the configuration phase, the coordinator activatesthe first subscriber via the first signal line and transmits a telegramcontaining a first subscriber address via the at least one bus line toall subscribers and thus to the first and the second subscribers. Thefirst subscriber stores the first subscriber address in a first volatilememory of the first subscriber. Advantageously, only the firstsubscriber stores the first subscriber address provided via the at leastone bus line, since only the first subscriber is activated. Such atelegram that is sent to all subscribers via the bus line can also bereferred to as a broadcast message. Since the first subscriber nowcontinues to store the first subscriber address in the first volatilememory in the operating phase that was initiated by the configurationphase, it can be addressed by means of the first subscriber address. Theactivation of the first subscriber can be done directly by thecoordinator or, if an additional or further subscribers are arrangedbetween the coordinator and the first subscriber, via the subscriberpreceding the first subscriber.

In one embodiment, the first subscriber activates the second subscribervia the second signal line in the configuration phase. Furthermore, thecoordinator transmits a message containing a second subscriber addressto all subscribers via the at least one bus line. The second subscriberstores the second subscriber address in a second volatile memory of thesecond subscriber. Advantageously, only the second subscriber stores thesecond subscriber address, since only the second subscriber is activatedat this point in time.

In one embodiment, the coordinator detects a malfunctioning of the firstand/or the second subscriber and stores the information about themalfunctioning of the first and/or the second subscriber in thenon-volatile semi-permanent memory. The coordinator registers themalfunctioning subscribers as having malfunctioned. The malfunctioningof a subscriber can be triggered by a defect in the subscriber, forexample, or as a result of the removal of the subscriber and thus theabsence of the subscriber. Both the associated serial number as well asinformation regarding whether the subscriber is down or whether it isactive is thus stored in the non-volatile semi-permanent memory of thecoordinator for each subscriber address.

In one embodiment, the coordinator can reactivate one or moresubscribers that malfunctioned. The activation can be performed in theforward direction as well as in the reverse direction. The subscribersof the first subscriber arrangement, such as the second subscriber, forexample, can be reactivated automatically by the coordinator.

In one embodiment, however, the first subscriber cannot be automaticallyactivated by the coordinator after a malfunction. In the event of themalfunctioning of the first subscriber, the coordinator outputs a signalwith a first error message, for example, and/or puts the bus arrangementinto a secure state.

In one embodiment, for example, the second subscriber is down and thefirst subscriber is functional. After the storage of the informationregarding the malfunctioning of the second subscriber, the coordinatorcan instruct the first subscriber to activate the second subscriber viathe at least one bus line. The coordinator can transmit a telegramcontaining the second subscriber address to all subscribers. Since thesecond subscriber is activated, the second subscriber stores the secondsubscriber address in the second volatile memory. The second subscriberthen confirms the activation to the coordinator. The coordinatorretrieves the serial number of the second subscriber and compares theretrieved serial number with the second serial number stored in thenon-volatile semi-permanent memory. If the two serial numbers match, thecoordinator can register the information about the operability of thesecond subscriber in the non-volatile semi-permanent memory.

Advantageously, the coordinator attempts to reincorporate the secondsubscriber into the bus operation. This prevents another subscriber frombeing connected to the bus in the place of the second subscriber. Thesecurity of the automation system is thus enhanced.

In one embodiment, the coordinator detects the malfunctioning of theadditional subscriber and stores the information regarding themalfunctioning of the additional subscriber in the non-volatilesemi-permanent memory. The additional subscriber is the directpredecessor of the first subscriber on the bus. After the storage of theinformation regarding the malfunctioning of the additional subscriber,the coordinator can direct a telegram to the serial number of theadditional subscriber via the at least one bus line and thus instructthe additional subscriber to activate the first subscriber. The firstsubscriber confirms the activation to the coordinator.

For example, the coordinator can transmit a telegram that is addressedto the serial number of the additional subscriber and contains thesubscriber address of the additional subscriber. Since the secondsubscriber is addressed via its serial number, the additional subscriberstores its subscriber address in a volatile memory. The coordinator canstore the information regarding the operability of the additionalsubscriber in the non-volatile semi-permanent memory.

Advantageously, the coordinator attempts to reincorporate the additionalsubscriber into the bus operation. However, it is only reintegrated intothe bus operation if its geographical position on the bus has beenidentified with the aid of the first subscriber. This prevents someother subscriber from being connected to the bus in the place of theadditional subscriber. The security of the automation system is thusenhanced. The coordinator performs backward addressing of the additionalsubscriber via the first subscriber.

In one embodiment, the first signal line connects the first subscriberto the coordinator. The first subscriber and the coordinator are thusdirectly and permanently connected to one another via the first signalline.

In one embodiment, the second subscriber is directly and permanentlyconnected to the first subscriber via the second signal line. The secondsubscriber is not directly connected to the first signal line. Thesecond subscriber is exclusively connected to the first signal line viathe first subscriber. Accordingly, the coordinator is not directlyconnected to the second signal line. The coordinator is coupled with thesecond signal line via the first subscriber.

The coordinator as well as the first subscriber and the secondsubscriber are directly connected to the at least one bus line.

In one embodiment, the at least one bus line of the bus is embodied asexactly one bus line.

In an alternative embodiment, the bus has the at least one bus line aswell as an additional bus line. Thus, the bus has exactly two bus lines,namely a first and a second bus line. The first and second bus lines canbe operated according to the TIA/EIA-485 A standard, also called EIA-485or RS-485.

In one embodiment, the bus arrangement includes one or more additionalsubscribers, which are connected to the at least one bus line. Anadditional subscriber can be connected to the second subscriber via athird signal line. However, the additional subscriber(s) can also bearranged between the coordinator and the first subscriber, for example.

In one embodiment, at least one of the subscribers is embodied as anactuator, measuring device, or sensor. The actuator can be a switchingdevice (such as a contactor, a motor starter, or a circuit breaker), afinal controlling device, a command device, a signaling device, acontrol unit (controller), or a frequency converter.

In one embodiment, the coordinator compares the first serial numberstored in the non-volatile semi-permanent memory with the second serialnumber stored in this memory. The coordinator provides a signaldepending on the result of the comparison. The signal thus representsinformation regarding whether the two serial numbers are identical. Ifthe serial numbers are identical, a fault condition is present.

In the event that the bus arrangement includes the first and the secondsubscriber as well as an additional subscriber with an additional serialnumber or a plurality of additional subscribers with a plurality ofadditional serial numbers, the coordinator compares the first and secondserial numbers and the additional serial number(s) with one another. Thecoordinator provides the signal representing the information that atleast two serial numbers are identical.

The first and second non-volatile permanent memories of the subscribersand a non-volatile permanent memory of the coordinator can, for example,be memories such as a read-only memory, abbreviated as ROM, aprogrammable read-only memory, abbreviated as PROM, or a one-timeprogrammable module—OTP module for short.

A first and a second non-volatile semi-permanent memory of thesubscribers and the non-volatile semi-permanent memory of thecoordinator can, for example, be memories such as electrically erasableprogrammable read-only memory, abbreviated as EEPROM, or a flash EEPROM.The first and second non-volatile semi-permanent memories of thesubscribers and the non-volatile semi-permanent memory of thecoordinator do not lose the content of their memory in a shut-downphase.

The first and second volatile memories of the subscribers and a volatilememory of the coordinator can be embodied as random access memory,abbreviated as RAM, or flash memory, for example. The RAM can beembodied as Dynamic Random Access Memory, abbreviated DRAM, or StaticRandom Access Memory, abbreviated SRAM. The first and second volatilememories and volatile memory of the coordinator lose the content oftheir memory in the shut-down phase.

In an embodiment, a method for operating a bus arrangement includes thesteps: A first subscriber arrangement is decoupled from a bus in anoperating phase. A coordinator continues to operate the bus arrangement.The bus arrangement includes the coordinator, the bus, the firstsubscriber, and the first subscriber arrangement with a secondsubscriber. The bus couples the coordinator with the first and secondsubscribers. The first subscriber is arranged between the coordinatorand the second subscriber on the bus.

Advantageously, the first subscriber arrangement can be decoupled duringongoing operation. Advantageously, the bus arrangement can have anexchange phase or exchange mode (“replacement mode”).

In one embodiment, when a first subscriber disconnects from the bus inan operating phase, the coordinator outputs a first error message and/orputs the bus arrangement into a secure state.

In one embodiment, the first subscriber arrangement is embodied as adrawer or sliding box. The bus arrangement is constructed in a cabinet,such as a control cabinet. The first subscriber arrangement can bepulled out and reinserted into the cabinet like a drawer or sliding box.

In one embodiment, it is possible to exchange the first subscriberarrangement both online and offline. No reconfiguration is necessary forthe exchange. A configuration phase is not required for the exchange.Subscriber arrangements behind one or more subscriber arrangementspulled at independent locations can also rejoin the bus after apower-up.

In one embodiment, the coordinator can address the first subscriber andthe second subscriber in the first subscriber arrangement by subscriberaddress and serial number. The subscriber address is assigned to aunique hardware serial number.

In one embodiment, the coordinator and subscribers form a seriesconnection or chain that can be referred to as a daisy chain. Thecoordinator and the subscribers thus form a daisy chain arrangement or adaisy chain bus. The coordinator and the subscribers are connected inseries via the signal lines. The first subscriber can be connecteddirectly to the coordinator. The other subscribers are each connected totheir predecessors.

Advantageously, subscribers can also be incorporated behind adaisy-chain signal gap without confusion. The first subscriber and,optionally, additional subscribers are installed in a geographicallyfixed manner and can also be used as a starting point for backwardaddressing.

The practicality of the automatic addressing of subscribers in a bussystem is advantageously improved by the bus arrangement and method.Automatic addressing offers a number of possibilities. For instance, adrawer that groups at least two subscribers together geographically inan ascending address sequence can be exchanged not only online but alsooffline without the need for the arrangement of a reconfiguration by thecoordinator. All drawers behind drawers that are pulled at independentlocations can also reconnect after a power-up.

The bus arrangement can also be referred to as a bus system. The busarrangement can carry out an addressing process by daisy chain and theunique serial number, thus enabling the correct positioning of asubscriber on the bus to be checked during a restart.

Each time the bus arrangement is first powered up, a daisy chainprocedure is used. All subscribers on the bus are addressed by thecoordinator with an ascending address sequence. In this method, a uniqueserial number that is stored on an integrated circuit that carries outthe bus communication, among other things, is retrieved by each bussubscriber. A globally unique number is stored on this integratedcircuit during the production process. The integrated circuit can beembodied as an application-specific integrated circuit, abbreviated asASIC. The integrated circuit can include the transceiver andnon-volatile permanent memory of the subscriber. Moreover, a deviceidentity (vendor, device) is read out, indicating the type of device(e.g. Eaton, switch, 200 amperes, type number). The addressing procedureends at the first missing subscriber or at the last possible subscriberto be addressed. The number of associated unique serial numbers of eachaddressed subscriber is remanently stored by the coordinator togetherwith its subscriber address.

By means of this method, bus segments, such as subscriber arrangements,for example, can be switched off, switched on again, and also exchangedin a dedicated exchange operating mode. The daisy chain represents thegeographical position, and the stored device identity (vendor, device)can be used for the replacement of the device in exchange operatingmode. The new serial number of the exchanged devices or subscribers arethen exchanged in the remanent configuration of the coordinator.

For example, when the coordinator restarts via the daisy chain, thehardware serial number of a subscriber that was identified during theinitial configuration is verified using the serial number storedremanently in the coordinator. This prevents misaddressing of asubscriber that was inserted in the incorrect place, for example. Allserial numbers in the bus array are checked in order to avoid duplicateaddressing.

If one or more subscribers are not recognized, e.g. due to aninterruption of the daisy chain (e.g. in the event of missing or faultysubscribers), addressing can be continued using the unique hardwareserial number at the first subscriber or another non-exchangeablesubscriber. This method is also used as an option in a subscriberarrangement during operation in the event of the malfunctioning ofsubscriber arrangements or subscribers in a subscriber arrangement andthe rejoining of subscriber arrangements or subscribers.

The invention is explained below in further detail on the basis ofseveral exemplary embodiments with reference to the figures. Componentsor functional units having the same function and/or effect bear the samereference numerals. Insofar as components or functional units havematching functions, a description thereof will not be repeated for eachone of the figures.

FIG. 1 shows an exemplary embodiment of a bus arrangement 10 thatincludes a first and a second subscriber 11, 12, a coordinator 13, and abus 14. The coordinator 13 is connected to the first and secondsubscribers 11, 12 via the bus 14. The first and second subscribers 11,12 each have a processor core 15, 16. The bus 14 includes a first signalline 17, which connects a terminal of the coordinator 13 to a terminalof the first subscriber 11 and thereby connects to a terminal of theprocessor core 15 of the first subscriber 11, for example. The firstsignal line 17 is not connected directly to the second or additionalsubscriber 12. For the sake of clarity, the lines in the coordinator 13and in the first and second subscribers 11, 12 are not shown.

Furthermore, the bus 14 includes a second signal line 18, which connectsa terminal of the first subscriber 11 to a terminal of the secondsubscriber 12. For example, the second signal line 18 connects theprocessor core 15 of the first subscriber 11 to the processor core 16 ofthe second subscriber 12. In addition, the bus 14 may include a thirdsignal line 19 connecting a terminal of the second subscriber 12 to athird subscriber (not shown). The coordinator 13 includes a processorcore 20, which is connected to the first signal line 17. The bus 14 isembodied as a linear bus. The bus 14 can be embodied as a serial bus.The coordinator 13 can be embodied as a master. The subscribers 11, 12can be embodied as slaves or devices. The processor core 15, 16, 20 canbe embodied as a microprocessor.

The bus arrangement 10 includes a first subscriber arrangement 23, whichincludes at least the second subscriber 12. It can also include thethird subscriber, for example (not shown). The bus arrangement 10 isconfigured such that the first subscriber arrangement 23 can bedecoupled from the bus 14 in an operating phase B. On the other hand,the bus arrangement 10 is not configured such that the first subscriber11 can be decoupled from the bus 14 in an operating phase B, at leastnot without triggering a first error message and/or the switching-off ofthe bus arrangement 10.

The processor core 20 of the coordinator 13 is connected via a signalline circuit 31 of the coordinator 13 to the first signal line 17.Furthermore, the processor core 15 of the first subscriber 11 isconnected via a signal line circuit 32 of the first subscriber 11 to thefirst and the second signal lines 17, 18. The processor core 16 of thesecond subscriber 12 is connected via a signal line circuit 33 of thesecond subscriber 12 to the second and, if present, also to the thirdsignal line 18, 19.

Moreover, the bus 14 includes at least one bus line 21 that connects thecoordinator 13 to all subscribers and thus to the first and secondsubscribers 11, 12. A signal on the at least one bus line 21 reaches allsubscribers 11, 12. The bus 14 may include an additional bus line 22connecting the coordinator 13 to all subscribers 11, 12. The at leastone bus line 21 and the additional bus line 22 can also be referred toas first and second bus lines. The coordinator 13 includes a transceiver24 that couples the processor core 20 with the first and second buslines 21, 22. The first and second subscribers 11, 12 also each includea transceiver 25, 26 with two terminals that are connected to the firstand second bus lines 21, 22. In the first and second subscribers 11, 12,the transceiver 25, 26 is coupled with the respective processor core 15,16. The first and second bus lines 21, 22 as well as the transceivers24-26 of the coordinator 13 and subscribers 11, 12 can be embodiedaccording to the TIA/EIA-485 A interface standard, also referred to asEIA-485 or RS-485. The transceivers 24-26 of the coordinator 13 andsubscribers 11, 12 can be embodied as bus transceivers or as transmitand receive transceivers and be designed for half-duplex operation.

In addition, the bus 14 includes a supply line 27 that connects a powersupply 28 of the coordinator 13 to a power supply 29 of the firstsubscriber 11 and a power supply 30 of the second subscriber 12. Eachpower supply 28, 29, 30 can be embodied as a voltage regulator.

Furthermore, the first and the second subscribers 11, 12 can each havean application device 35, 36. The application device 35, 36 can beembodied as an actuator, measuring device, or sensor device. The firstand second subscribers 11, 12 can thus be embodied as an actuator,measuring device, and/or sensor. The application device 35 of the firstsubscriber 11 is coupled with the processor core 15 of the firstsubscriber 11. The same applies to the second subscriber 12.Furthermore, the bus 14 includes a reference potential line 42 thatconnects a reference potential terminal of the coordinator 13 toreference potential terminals of the first and second subscribers 11,12. The power supply line 27 and the reference potential line 42 serveto supply power to the subscribers 11, 12 through the coordinator 13.

Moreover, the coordinator 13 includes a memory 53 that is connected tothe processor core 20 or microcontroller 34 of the coordinator 13. Thememory 53 can be embodied as a non-volatile semi-permanent memory.Furthermore, the coordinator 13 includes a volatile memory 52. The firstsubscriber 11 includes a first volatile memory 54, a first non-volatilepermanent memory 55, and a first non-volatile semi-permanent memory 55′.The memories 54, 55 can be connected to the transceiver 25. The secondsubscriber 12 includes a second volatile memory 56, a secondnon-volatile permanent memory 57, and a second non-volatilesemi-permanent memory 57′. The memories 56, 57 can be connected to thetransceiver 26.

The transceiver 25 of the first subscriber 11 recognizes a firstsubscriber address that is stored in the first volatile memory 54 and afirst serial number that is stored in the first non-volatile permanentmemory 55, so that the first subscriber 11 processes the data in thetelegram. The first subscriber 11 can thus be addressed by a telegramcontaining only the first subscriber address and data, as well as by atelegram containing only the first serial number and data. The firstsubscriber 11 can thus be addressed in two ways via the at least one busline 21. In addition, the first subscriber 11 can also be activated viathe first signal line 17. The second subscriber 12 can also identify thesecond subscriber address that is stored in the second volatile memory56 and the second serial number that is stored in the secondnon-volatile permanent memory 57, so that the second subscriber 12processes the data in the telegram.

The coordinator 13 includes an integrated circuit 45, which can beembodied as an ASIC. The integrated circuit 45 can include the powersupply 28, the transceiver 24, the signal line circuit 31, the volatilememory 52, and the processor core 20. Moreover, the first and secondsubscribers 11, 12 each include an integrated circuit 46, 47, which canbe embodied as an ASIC. The integrated circuit 46 of the firstsubscriber 11 can include the power supply 29, the transceiver 25, thesignal line circuit 32, the first volatile memory 54, the firstnon-volatile permanent memory 55, the first non-volatile semi-permanentmemory 55′, and the processor core 15. Accordingly, the integratedcircuit 47 of the second subscriber 12 can include the power supply 30,the transceiver 26, the signal line circuit 33, the second volatilememory 56, the second non-volatile permanent memory 57, the secondnon-volatile semi-permanent memory 57′, and the processor core 16.

The coordinator 13 includes an additional transceiver 58, which couplesan additional bus terminal 59 of the coordinator 13 with themicrocontroller 34. The coordinator 13 includes a switch 49. The switch49 can be embodied as a button. The switch 49 can be actuated by anoperator. Furthermore, the bus arrangement 10 includes a fieldbus 60,which is connected to the additional bus connection 59. The coordinator13 can be a gateway, router, or switch. The coordinator 13 has anoscillator 50. The oscillator 50 can be embodied as an RC oscillator.The oscillator 50 can be used for time control. The coordinator 13 canhave a non-volatile permanent memory 51 or an additional memory that isembodied as RAM or flash memory. A control 61 of the bus arrangement 10can be connected to the fieldbus 60, for example.

The bus 14 is embodied as a ribbon cable or round cable. According toFIG. 1, the bus 14 can consist of five wires, for example.Alternatively, the bus 14 can have a different number of wires, e.g.eight wires. The functionality of the bus arrangement 10 according toFIG. 1 will be explained in greater detail with reference to thefollowing figures.

FIG. 2 shows an exemplary embodiment of a bus arrangement 10, which is adevelopment of the bus arrangement shown in FIG. 1. The bus arrangement10 includes the coordinator 13, the first subscriber 11, and the firstsubscriber arrangement 23. The first subscriber arrangement 23 includesthe second subscriber 12 and a third to a seventh subscriber 70-74. InFIG. 2, the subscriber address is indicated in the respectivesubscriber. Since the first subscriber 11 is directly and immediatelyconnected to the coordinator 13, the first subscriber 11 bears the firstsubscriber address “1.” Accordingly, the second to seventh subscribers12, 70-74 bear the subscriber addresses “2” to “7.” The coordinator 13numbers the subscribers 11, 12, 70-74 consecutively.

The at least one bus line 21 and the additional bus line 22 areconnected to all subscribers 11, 12, 70-74. Each of the subscribers 11,12, 70-74 is connected on the input side via a signal line to thepreceding subscriber and on the output side via a signal line to thesubsequent subscriber. Thus, for example, the third subscriber 70 isconnected on the input side via the third signal line 19 to the secondsubscriber 12 and via a fourth signal line 75 to the fourth subscriber71.

The bus arrangement 10 further includes an eighth subscriber 76. Theeighth subscriber 76 is embodied like the first subscriber 11. The busarrangement 10 is configured to incorporate an additional subscriberarrangement 77 that can be connected to the eighth subscriber 76. Theadditional subscriber arrangement 77 is shown in dashed lines. Theadditional subscriber arrangement 77 that can be connected to the eighthsubscriber 76 could have a ninth to a fourteenth subscriber, forexample. The eighth subscriber 76 is connected on the input side via asignal line 78 to the output of the seventh subscriber 74. In the stateof the bus arrangement 10 that is shown in FIG. 2, the eighth subscriber76 is not connected to any additional subscriber on the output side viaa signal line 79. On the output side, however, a ninth subscriber couldbe connected to the eighth subscriber 76 via a signal line 79.

Moreover, the bus arrangement 10 includes a fifteenth subscriber 80whose input could be connected via an additional signal line 81 to thefourteenth subscriber. However, since the additional subscriberarrangement 77 including the ninth through fourteenth subscribers ismissing, a gap—also called a daisy chain gap or signal line interruption(selection disruption)—arises between the eighth subscriber 76 and thefifteenth subscriber 80. An additional subscriber arrangement 82 isconnected to the fifteenth subscriber 80. The additional subscriberarrangement 82 includes a sixteenth to a twenty-first subscriber 83 to88. The sixteenth to the twenty-first subscribers 83 to 88 are eachconnected on the input side via a signal line to the precedingsubscriber and on the output side via a signal line to the subsequentsubscriber.

Furthermore, the bus arrangement 10 includes a twenty-second subscriber90, to which an additional subscriber arrangement 91, which includes atwenty-third to a twenty-eighth subscriber, can be connected. Theadditional subscriber arrangement 91 is absent in the exemplary state ofthe bus arrangement 10 that is shown in FIG. 2.

Moreover, the bus arrangement 10 shows a twenty-ninth subscriber 92 aswell as another additional subscriber arrangement 93 having a thirtiethto a thirty-fifth subscriber 94 to 99, a thirty-sixth subscriber 100, aswell as another additional subscriber arrangement 101 having athirty-seventh to a forty-third subscriber 102 to 108. All of thesubscribers of the bus arrangement 10 are connected directly to the atleast one bus line 21 and the additional bus line 22. Each of thesesubscribers can thus be addressed via its subscriber address as soon asthe coordinator 13 has assigned its subscriber address to the subscriberin the configuration phase K. Furthermore, each of the subscribers isconnected on the input side via a signal line to its precedingsubscriber, provided that it is not absent, and is connected on theoutput side via a signal line to the subsequent subscriber, providedthat it is not absent.

The first, eighth, fifteenth, twenty-second, twenty-ninth, andthirty-sixth subscribers 11, 76, 80, 90, 92, 100 cannot be decoupledfrom the bus 14 in an operating phase B. These subscribers are theso-called permanently mounted (fix-mounted) subscribers. On the otherhand, the first subscriber arrangement 23 and the additional subscriberarrangements 77, 82, 91, 93, 101 can be decoupled from the bus 14 in anoperating phase B. The subscriber arrangements 23, 77, 82, 91, 93, 101can be removed and exchanged during operation, meaning that they arehot-pluggable. The subscriber arrangements 23, 77, 82, 91, 93, 101 canalso be referred to as drawers.

In an alternative embodiment (not shown), the first subscriberarrangement 23 or one of the additional subscriber arrangements 77, 82,91, 93, 101 has a different number of subscribers than shown in FIG. 2.For example, the first or one of the additional subscriber arrangements23, 77, 82, 91, 93, 101 can have at least one subscriber, i.e. thesecond subscriber 12. Alternatively, the first or one of the additionalsubscriber arrangements 23, 77, 82, 91, 93, 101 can have at least twosubscribers 12, 70.

By means of the addressing method utilizing the unique ASIC serialnumber that is assigned to each subscriber 11, 12 and thus to eachsubscriber address, gaps in the daisy chain can be bridged if theconfiguration was previously read in once in a remanently unchangeablemanner in the configuration phase K. The switch 49, also known as theconfiguration button, can be actuated in order to initiate theconfiguration phase K. Subscribers behind a select signal gap are alsoreconnected.

The bus arrangement 10 enables a hot-plugging procedure: duringmaintenance, new subscribers with new serial numbers can be used andthese can be incorporated via the daisy chain in an exchange operatingphase.

The bus arrangement 10 is secure even if several subscribers areexchanged and an interruption of the daisy chain is also produced beforethe exchanged elements. In this case, the coordinator 12 generates anerror message and/or puts the bus arrangement 10 into a secure state.

An exchange operating phase, also called replacement mode, provides forthe identification of the drawers 23, 77, 82, 91, 93, 101 and theirsubscribers, which can be exchanged online or offline. Since the drawers23, 77, 82, 91, 93, 101 with their subscribers and their position in thebus arrangement 10 (i.e. in the cabinet) can be unambiguouslydetermined, good manageability is ensured with a high level of security.In order to enable the beginning of the respective drawer to bedetermined unambiguously on the bus 14, a subscriber type—e.g. the firstsubscriber 11—is installed in the power supply branch components andsignals this branch position on the bus line. The first subscriber 11remains permanently installed in the cabinet and can only be exchangedoffline and by means of an additional configuration phase K′.

The first subscriber 11 can also be addressed in the exchange operatingphase on the basis of the ASIC serial number and thus also be addressedif a draw is pulled in front of it (daisy chain interruption). The puredaisy-chain addressing for the hot-pluggable subscribers of subscriberarrangements 23, 77, 82, 91, 93, 101 can be started separately betweenthese permanently installed subscribers 11, 76, 80, 90, 92, 100.

In addition, the integrated circuit 46 in the first subscriber 11 canmeasure the outgoing current of the 15 volt bus supply 27, 42 and thusidentify whether the first subscriber arrangement 23, i.e. the drawer,to be supplied with power is mechanically plugged in and whether a firstattempt to reconnect the first subscriber arrangement 23 is at allworthwhile. The integrated circuit 45 measures the current flowing onthe supply line 27 to the first subscriber arrangement 23. If a currentis flowing, the coordinator 13 attempts to reactivate the firstsubscriber arrangement 23. Reconnection can thus be optimized.

In addition, an offline exchange can be performed. The drawers 23, 77,82, 91, 93, 101 can also be replaced in the shut-down state, that is,they can be not only hot-pluggable online. The bus arrangement 10 iscapable of installing and starting the gateway 13 elsewhere (in othercabinet) of compatible structure and recognizing the new subscribers.

After power-up, the exchange mode is detected in the targetconfiguration. The permanently installed subscribers 11, 76, 80, 90, 92,100 are the first to be checked directly for the serial number. As inthe case of online exchanging as well, if all of these specialsubscribers 11, 76, 80, 90, 92, 100 are present in the desiredconfiguration (cabinet recognition), the reconnection or the compatibleexchange of the subscribers for one subscriber arrangement 23 (alsocalled segment or drawer) can be initiated through selection via thedaisy chain. The next drawer 23, 77, 82, 91, 93, 101 is then processedby means of the next first drawer subscriber 11, 76, 80, 90, 92, 100.

A startup is also possible with a missing first drawer 23. If the firstsubscriber 11 cannot be recognized on the bus 14, the coordinator 13usually goes into a fault state without bus activity that can only beexited via a reset. Once the online exchange has been configured, thisfinal fault state is exited and the recovery process (regain-automat) is(is always) initiated. The coordinator 13 thus begins with thepermanently installed first subscribers 11, 76, 80, 90, 92, 100 withserial number addressing and then tries the subscribers 12, 70-74, etc.of the individual drawers 23, 77, 82, 91, 93, 101 in ascending order viathe signal lines before starting again at the next drawer branch.

The bus arrangement 10 can perform logical backward addressing by fixedreference point, serial number, and daisy chain control.

In a hot-pluggable bus system 10 in which subscribers can be exchanged,the serial number can no longer be used for the simple bridging of adaisy chain gap. Subscribers behind the gap can no longer be easilyaddressed without the possibility of confusion and hence vulnerability.Therefore, in the event of a gap in the bus arrangement 10, thegeographically nearest permanently installed subscriber—among thesubscribers 11, 76, 80, 90, 92, 100, for instance—is used as a startingpoint for logical backward addressing and attempts to address thesubscribers before the geographical starting point by serial number, tocheck their position by means of signal lines, and only then to activatethem. The first subscriber 11 and the subscribers 76, 80, 90, 92, 100are not hot-pluggable.

The addressing of the subscribers 12, 70-74 of the first subscriberarrangement 23 can also be attempted between two permanently installednon-hot-pluggable subscribers 11, 76 on the basis of a serial number;however, geographical position must be additionally checked by means ofthe signal lines before the subscribers 12, 70-74 of the firstsubscriber arrangement 23 may be activated. Addressing can also beperformed backward from a starting point, meaning that an attempt ismade to address the preceding serial number and set its signal line inorder to then also check its real geographical position in thesubscriber behind it (fixed in the first pass) by signal line. This canbe done backwards from subscriber to subscriber until a signal line gapis reached.

The coordinator 13 knows the permanently installed, non-exchangeablesubscribers 11, 76, 80, 90, 92, 100 and, in starting from these, it cannot only reinitiate the signal line addressing but also attempt toaddress them backwards geographically by serial number and to also checktheir geographical position prior to activation. This makes it possibleto check the backward serial number addressing using the daisy chain.

FIG. 3A to 3H show an exemplary embodiment of a bus arrangement 10,which is a development of the embodiments shown in FIGS. 1 and 2. Thebus arrangement 10 includes the coordinator 13, the first and the secondsubscribers 11, 12, as well as a third and a fourth subscriber 70, 71.The first subscriber arrangement 23 includes the second and thirdsubscribers 12, 70. In contrast to FIG. 2, the fourth subscriber 71 isembodied like the first subscriber 11 and cannot be removed duringongoing operation. The coordinator 13 is connected directly to the firstsubscriber 11 via the first signal line 17. The first subscriber 11 isconnected via the second signal line 18 directly to the secondsubscriber 12. Accordingly, the second subscriber 12 is connected viathe third signal line 19 directly to the third subscriber 70.Furthermore, the third subscriber 70 is connected to the fourthsubscriber 71 via the fourth signal line 75. The first to the fourthsignal lines 17, 18, 19, 75 form a daisy chain. Moreover, thecoordinator 13 is connected directly to all subscribers 11, 12, 70, 71via the at least one bus line 21 and the additional bus line 22, whichare also referred to as first and second bus line.

In FIG. 3A, the bus arrangement 10 is shown in a shut-down phase A. Theshut-down phase A can come before an operating phase B, for example,which begins with a configuration phase K. Alternatively, the switch-offphase A may come before an additional operating phase B′, which beginswith a restart phase W. The coordinator 13 has an address of 0, forexample. No subscriber addresses are stored in the first to fourthsubscribers 11, 12, 70, 71. In FIG. 3B to 3E, the subscribers 11, 12,70, 71 are addressed successively from left to right via the coordinator13 and with the aid of the daisy chain, and the geographical positionsand thus the sequence of the subscribers 11, 12, 70, 71 are established.

In an alternative embodiment that is not shown, the coordinator 13 iscoupled with the first subscriber 11 via the first signal line 17 andone or more additional subscribers and one or more additional signallines.

FIG. 3B shows the bus arrangement 10 according to FIG. 3A in theconfiguration phase K. The coordinator 13 activates the first subscriber11 via the first signal line 17. To indicate the activation, the firstsignal line 17 is shown in dashed lines. After activation, thecoordinator 13 transmits a telegram containing a first subscriberaddress to all subscribers 11, 12, 70, 71 via the first and second buslines 21, 22. Only the activated subscriber, namely the first subscriber11, incorporates the first subscriber address contained in the telegraminto its volatile memory 54. The first subscriber address can be 1.

As explained, the coordinator 13 sets its daisy chain and transmits thesubscriber address 1 to be assigned as a broadcast via the RS-485 busline/data line 21, 22 of the bus 14 to all subscribers 11, 12, 70, 71.At this point in time, only the daisy chain is active at the firstsubscriber 11, for which reason it interprets subscriber address withthe number 1 received from the coordinator 13 as being its own. Fromthis point forward, the first subscriber 11 can receive bus messageswith the previously received subscriber address.

FIG. 3C shows the bus arrangement 10 that was already shown in FIGS. 3Aand 3B in an additional step of the configuration phase K. Thecoordinator 13 establishes a connection to the first subscriber 1 viathe first and second bus lines 21, 22 in order to read out a firstserial number of the first subscriber 11. For this purpose, thecoordinator 13 transmits a telegram to the first subscriber address thatincludes the command to provide the serial number. The transceiver 25 ofthe first subscriber 11 recognizes that the first subscriber 11 is beingaddressed and causes the processor core 15 of the first subscriber 11 totransmit, via the first and second bus lines 21, 22, the first serialnumber to the coordinator 13, which stores it in the non-volatilesemi-permanent memory 53. As a result, the first subscriber 11 isregistered in the coordinator 13.

In FIG. 3C, the coordinator 13 is able to establish a connection to thefirst subscriber 11 and to retrieve its data. Among other things, thefirst serial number is read out and linked in the coordinator 13 withthe associated first subscriber address and remanently stored. The daisychain is reset.

FIG. 3D shows the bus arrangement 10 that is already shown in FIG. 3A to3C in an additional step in the configuration phase K. The coordinator13 transmits a telegram to the first subscriber 11 with the command toactivate the output-side signal line, i.e. the second signal line 18.The first subscriber 11 detects by means of its transceiver 25 that itis being addressed and activates the second subscriber 12 via a signalon the second signal line 18. Subsequently, the coordinator 13 transmitsa telegram to all subscribers 11, 12, 70, 71 that contains the secondsubscriber address, e.g. 2. However, since only the second subscriber 12is activated, only the second subscriber 12 incorporates the secondsubscriber address into its volatile memory 56. As an additional step inthe configuration phase K, the coordinator 13 causes the secondsubscriber 12 to make the second serial number available. The secondsubscriber 12 is registered by storing the second serial number in thenon-volatile semi-permanent memory 53 of the coordinator 13.

In FIG. 3D, the first subscriber 11 receives the order to set its daisychain so that the addressing can be continued. The coordinator 13 sendsa broadcast with the subscriber address 2 included. This procedure iscarried out by the coordinator 13 until all subscribers have beenassigned a subscriber address. Consequently, the third subscriber 70 isactivated and assigned a third subscriber address 3, for instance and athird serial number of the third subscriber 70 is retrieved. The fourthsubscriber 71 carries out corresponding steps.

FIG. 3E shows the bus arrangement 10 that is already shown in FIG. 3A to3D in the operating phase after completion of the configuration phase K.The coordinator 13 is now able to address all subscribers 11, 12, 70, 71via the subscriber addresses. The addressed subscribers 11, 12, 70, 71are stored remanently in the coordinator 13 together with parameter andconfiguration data (serial numbers, vendor identity). Previouslyidentified subscribers 11, 12, 70, 71 can be addressed again by thecoordinator 13 by their unique serial number even after malfunctions.The addressed subscribers 11, 12, 70, 71 do not remanently store theirsubscriber addresses, behaving again as in the beginning (like in FIG.3A, for example) after another power-up.

FIG. 3F shows the bus arrangement 10 that is already illustrated in FIG.3A to 3E in the operating phase B. Subscribers can drop out in theoperating phase B. In the example shown in FIG. 3F, the second and thirdsubscribers 12, 70 have malfunctioned. The coordinator 13 is still ableto send telegrams to the subscribers 11, 71 that have not malfunctionedvia the first and second bus lines 21, 22 and to control the subscribers11, 71 that have not malfunctioned or to retrieve their data. Thecoordinator 13 detects the malfunctioning of the subscribers in thiscase, the second and third subscribers 12, 70 and stores informationregarding the malfunction of the malfunctioning subscribers 12, 70 inthe non-volatile semi-permanent memory 53, registering them as havingmalfunctioned.

The bus arrangement 10 continues even after the malfunctioning ofsubscribers 12, 70. The coordinator 13 assumes the role of themalfunctioning subscribers 12, 70. The volatile memory 54, 56 of themalfunctioning subscriber(s) 12, 70 generally loses its subscriberaddress during the failure.

The coordinator 13 is configured so as to reactivate one or moremalfunctioning subscribers acyclically or at predetermined times, forexample. A malfunctioning subscriber can be repaired in a shut-downphase A, for example. In one embodiment, the malfunctioning subscribercan also be removed in an operating phase B and used again after repair.This procedure is called hot-plugging.

FIG. 3G shows the exemplary bus arrangement 10 as already shown in FIG.3A to 3F in a part of the operating phase B. As shown in FIG. 3F, twosubscribers namely, the second and third subscribers 12, 70 have droppedout. Only the third subscriber 70 is available again and is to bereconnected. For the purpose of activation, the coordinator 13 transmitsa message via the first and second bus lines 21, 22 with the serialnumber of the malfunctioning subscriber, i.e. with the serial number ofthe third subscriber 70. For example, the third subscriber 70 canconfirm receipt of the message to the coordinator 13. The coordinator 70transmits a telegram to the malfunctioning subscriber 70 with thecommand that it output a signal on its output-side signal line to thesubsequent subscriber 71.

In the example of FIG. 3G, the third subscriber 70 transmits a signal tothe fourth subscriber 71 via the fourth signal line 75. The subscriber71 that is on the bus 14 after the malfunctioning subscriber 70transmits its activation to the coordinator 13. The coordinator 13transmits the third subscriber address to the third subscriber 70, forexample by means of a telegram that is addressed to the third serialnumber. This ensures that the subscriber that has the third serialnumber is not secured just anywhere on the bus 14 when it is switchedback on, but rather at the correct location, namely immediately beforethe fourth subscriber 71.

The fourth subscriber 71 is a permanently installed subscriber. Sinceits location on the bus is unique, it is ensured through the use of thethird serial number that the correct subscriber is installed at theposition of the third subscriber 70.

As described above, recurrent subscribers 70 can be addressed by thecoordinator 13 based on the unique serial number even without a daisychain. However, the daisy chain of the detected subscriber 70 is thenused as an aid in determining the geographical positions. Thus, afteractivation of the daisy chain from the third subscriber 70 to the fourthsubscriber 71, the geographical location of the third subscriber 70 canbe confirmed again.

FIG. 3H shows the bus arrangement 10 that is already shown in FIG. 3A to3G after execution of the steps illustrated by FIG. 3G. The thirdsubscriber 70 has now received its subscriber address 3 back and can bereintegrated into the bus arrangement 10. The coordinator 13 storesinformation in its non-volatile semi-permanent memory 53 that the thirdsubscriber 70 is active.

FIG. 4 shows an exemplary embodiment of the chronological sequence ofthe phases. The different phases are plotted over a time t. Theconfiguration phase K is carried out at the beginning of the operatingphase B. After the coordination phase K has been carried out, forexample, regular operation of the bus arrangement 10 is carried out inthe operating phase B. The operating phase B is followed by a shut-downphase A. In the shut-down phase A, the coordinator 13 and thesubscribers 11, 12 are not supplied with electric power. The shut-downphase A is followed by an additional operating phase B′. At thebeginning of the additional operating phase B′, a restart phase W iscarried out. After the restart phase W, the regular operation of the busarrangement 10 is carried out in the additional operating phase B′. Theadditional operating phase B′ can be followed by additional shut-downphases A and additional operating phases B″.

One of the additional operating phases B″ can begin with an additionalconfiguration phase K′, for example. For example, an operator can resetthe bus arrangement 10 by means of the switch 49 of the coordinator 13,so that the bus arrangement 10 starts with the additional configurationphase K′.

The malfunctioning of subscribers and the activation of subscribersillustrated in FIG. 3F to 3G can occur in each of the operating phasesB, B′, B″.

In the restart phase W, the coordinator 13 carries out steps to assignthe subscriber addresses to the subscribers that are similar to thosecarried out in the configuration phase K. In addition, the coordinator13 performs a comparison of the serial numbers retrieved in the restartphase W with the serial numbers stored in its non-volatilesemi-permanent memory 53.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, such illustration and descriptionare to be considered illustrative or exemplary and not restrictive. Itwill be understood that changes and modifications may be made by thoseof ordinary skill within the scope of the following claims. Inparticular, the present invention covers further embodiments with anycombination of features from different embodiments described above andbelow. Additionally, statements made herein characterizing the inventionrefer to an embodiment of the invention and not necessarily allembodiments.

The terms used in the claims should be construed to have the broadestreasonable interpretation consistent with the foregoing description. Forexample, the use of the article “a” or “the” in introducing an elementshould not be interpreted as being exclusive of a plurality of elements.Likewise, the recitation of “or” should be interpreted as beinginclusive, such that the recitation of “A or B” is not exclusive of “Aand B,” unless it is clear from the context or the foregoing descriptionthat only one of A and B is intended. Further, the recitation of “atleast one of A, B and C” should be interpreted as one or more of a groupof elements consisting of A, B and C, and should not be interpreted asrequiring at least one of each of the listed elements A, B and C,regardless of whether A, B and C are related as categories or otherwise.Moreover, the recitation of “A, B and/or C” or “at least one of A, B orC” should be interpreted as including any singular entity from thelisted elements, e.g., A, any subset from the listed elements, e.g., Aand B, or the entire list of elements A, B and C.

The following is a list of reference numerals:

-   10 bus arrangement-   11 first subscriber-   12 second subscriber-   13 coordinator-   14 bus-   15, 16 processor core-   17 first signal line-   18 second signal line-   19 third signal line-   20 processor core-   21 at least one bus line-   22 additional bus line-   23 first subscriber arrangement-   24, 25, 26 transceiver-   27 power supply line-   28, 29, 30 power supply-   31, 32, 33 signal line circuit-   34 microcontroller-   35, 36 application device-   42 reference potential line-   45, 46, 47 integrated circuit-   49 switch-   50 oscillator-   51 non-volatile permanent memory-   52 volatile memory-   53 non-volatile semi-permanent memory-   54 first volatile memory-   55 first non-volatile permanent memory-   55′ first non-volatile semi-permanent memory-   56 second volatile memory-   57 second non-volatile permanent memory-   57′ second non-volatile semi-permanent memory-   58 additional transceiver-   59 additional bus connection-   60 fieldbus-   70-74 subscribers-   75 signal line-   76 subscriber-   77 additional subscriber arrangement-   78, 79 signal line-   80, 83-88 subscribers-   81 signal line-   82 additional subscriber arrangement-   90 subscriber-   91 subscriber arrangement-   92, 94-99 subscribers-   93 another additional subscriber arrangement-   100, 102-108 subscribers-   101 another additional subscriber arrangement-   A shut-down phase-   B, B′, B″ operating phase-   K configuration phase-   K′ additional configuration phase-   t time-   W, W′ restart phase

1: A bus arrangement, the bus arrangement comprising: a coordinator; afirst subscriber; a first subscriber arrangement with a secondsubscriber; and a bus coupling the coordinator with the first subscriberand the second subscriber, the first subscriber being arranged betweenthe coordinator and the second subscriber on the bus, wherein the busarrangement is configured such that the first subscriber arrangement canbe decoupled from the bus in an operating phase, and such that the firstsubscriber cannot be decoupled from the bus in the operating phase. 2:The bus arrangement according to claim 1, wherein the coordinator isconfigured to output a first error message and/or to put the busarrangement into a secure state when the first subscriber is active at afirst timepoint during the operating phase and has been removed or isinactive at a second timepoint during a same operating phase as theoperating phase, with the second timepoint coming after the firsttimepoint. 3: The bus arrangement according to claim 1, wherein thecoordinator is configured to register a decoupling of the secondsubscriber when the first subscriber is active at a first timepointduring the operating phase and has been removed or is inactive at asecond timepoint during a same operating phase as the operating phase,with the second timepoint coming after the first timepoint. 4: The busarrangement according to claim 1, wherein the first subscriber has afirst non-volatile permanent memory in which a first serial number isstored, and the second subscriber has a second non-volatile permanentmemory in which a second serial number is stored, and wherein thecoordinator is configured such that, in a configuration phase, itassigns a first subscriber address to the first subscriber, assigns asecond subscriber address to the second subscriber, retrieves the firstserial number and the second serial number, and stores the first serialnumber and the second serial number in a non-volatile semi-permanentmemory of the coordinator. 5: The bus arrangement according to claim 4,wherein the coordinator is configured such that, in a restart phase thatfollows the configuration phase, it establishes a connection to thefirst subscriber and the second subscriber, retrieves the first serialnumber and the second serial number, compares the retrieved first serialnumber and the retrieved second serial number with the first serialnumber and the second serial number stored in the non-volatilesemi-permanent memory, and outputs an error message if one or both ofthe retrieved first serial number or the retrieved second serial numberdeviates from the stored first serial number or the stored second serialnumber. 6: The bus arrangement according to claim 4, wherein the busarrangement is configured such that the first subscriber is exchangeablefor another first subscriber during a shut-down phase that comes betweenthe configuration phase and an additional configuration phase, andwherein the coordinator is configured such that, in the additionalconfiguration phase, it establishes a connection to the additional firstsubscriber, retrieves a serial number of the additional firstsubscriber, and stores the serial number of the additional firstsubscriber in the non-volatile semi-permanent memory. 7: The busarrangement according to claim 6, wherein the coordinator comprises aswitch and is configured to carry out the additional configuration phaseafter actuation of the switch. 8: The bus arrangement according to claim4, wherein the bus arrangement is configured such that an additionalsubscriber is connectible to the bus between the coordinator and thefirst subscriber during the configuration phase and removable after theconfiguration phase, and wherein the coordinator is configured suchthat, in a restart phase after the configuration phase, it addresses thefirst subscriber using the first serial number and assigns a firstsubscriber address to the first subscriber. 9: The bus arrangementaccording to claim 1, wherein the bus comprises a first signal line thatcouples the first subscriber and the coordinator, a second signal linethat connects the second subscriber to the first subscriber, and atleast one bus line that connects the coordinator to the first subscriberand the second subscriber, wherein the coordinator is configured suchthat, in a configuration phase, it activates the first subscriber viathe first signal line, and transmits a telegram containing the firstsubscriber address via the at least one bus line, and wherein the firstsubscriber is configured to store the first subscriber address in afirst volatile memory of the first subscriber. 10: The bus arrangementaccording to claim 9, wherein the first subscriber is configured suchthat, in the configuration phase, it activates the second subscriber viathe second signal line, wherein the coordinator is configured totransmit a telegram containing the second subscriber address via the atleast one bus line, and wherein the second subscriber is configured tostore the second subscriber address in a second volatile memory of thesecond subscriber. 11: A method for operating a bus arrangementcomprising a coordinator; a bus, a first subscriber; and a firstsubscriber arrangement with a second subscriber, the bus coupling thecoordinator with the first subscriber and the second subscriber, thefirst subscriber being arranged between the coordinator and the secondsubscriber on the bus, the method comprising: decoupling the firstsubscriber arrangement from the bus during an operating phase while thecoordinator continues to operate the bus arrangement; and upondecoupling of the first subscriber from the bus in the operating phase,outputting, by the coordinator, a first error message and/or putting, bythe coordinator, the bus arrangement into a secure state.